Senior Software Engineer (Payments & Incentives) in London

At Quantcast, we don't just build advertising technology, we revolutionize how it works. Our AI-powered Demand Side Platform (DSP) connects the world's most ambitious marketers with their ideal audiences across the open internet, delivering results that actually move the needle. Since 2006, we've been the industry's trailblazer, launching the first AI-powered measurement platform for publishers and the first AI-driven DSP. Our AI doesn't just optimize—it delivers the measurable outcomes that matter most to our clients, giving them the competitive edge they need in a crowded marketplace.

We are looking for a Senior Software Engineer to join the Payments & Incentives team. The team acts as the financial engine of Quantcast, managing the intersection of complex ad-tech data and precise fintech requirements. The team is responsible for building frictionless payment solutions for our users, operating incentive programs to increase customer retention, and managing internal systems that power the billing pipelines. Operating across multiple functional areas, the team bridges engineering with customer experience, support, and essential back-office functions such as finance and revenue operations.

You will be at the forefront of innovating solutions that integrate efficient payment, billing, and reward programs directly into our high-scale next generation advertising platform, focusing on making digital advertising campaigns as simple as possible for our customers. Our infrastructure handles diverse use cases, from real-time fee breakdowns for campaign forecasting and bidding to unified billing workflows that synchronize across application databases, Snowflake and NetSuite. We are currently refactoring these mission-critical pipelines to consolidate billing logic, which will enhance invoice visibility and traceability for revenue operations. These mission-critical systems enable global brands to scale their business with us.

What you'll do:

• Drive engineering initiatives for unified financial reporting and process consolidation, ensuring systems are reliable, monitored, and successfully adopted.
• Lead the design and implementation of robust microservices and APIs to handle payments, incentives, and billing processes.
• Continually engage with internal customers, product owners and business stakeholders to understand and resolve cross-team dependencies and end-user requirements.
• Support the professional development of your peers and junior members through constructive feedback on code, system design and engineering processes.
• Manage the resolution of complex on-call incidents, implementing measures to improve long-term system health and financial integrity.

You might be a great fit for this role if you:

• Focus on outcomes: You don’t claim victory at code completion; you measure success by positive business results and customer adoption.
• Operate with autonomy: You are comfortable taking high-level priorities and turning them into actionable, well-defined technical roadmaps without constant supervision.
• Bridge the gap: You enjoy deeply understanding the end-customer use case and translating those requirements into robust technical solutions.
• Advocate for excellence: You have a passion for mentoring others and are dedicated to maintaining high standards for code quality and operational reliability.

Who you are:

• You have at least 2 years of experience building and maintaining complex distributed systems, with a focus on microservices and adjacent technologies. Experience working vertically across the stack is a significant plus.
• You have a degree in Computer Science or an adjacent field (or equivalent nontraditional training).
• You are proficient in Go & Python or a similar modern language, or can demonstrate the ability to pick it up relatively speedily.
• You have experience designing and implementing APIs and microservices in a high-velocity production environment.
• You possess a deep understanding of observability and the full software development life cycle (SDLC) in an Agile environment.
• You can effectively distill complex technical updates into clear, actionable information for both technical and non-technical stakeholders.
• You excel at working across team boundaries and with third parties to untangle dependencies and move projects forward.
• Familiarity with cloud technologies (AWS), messaging systems (Kafka, SQS), or data warehouse tools (Snowflake) is a significant plus.

At Quantcast, we craft offers that reflect your unique skills, expertise, and geographic location. On top of a competitive salary, this position includes a performance bonus, equity, and a comprehensive benefits package. For more details, visit our Careers Page and see how we support our team. We are headquartered in San Francisco with offices around the world. Quantcast is an Equal Opportunity Employer.